JP2001018171A - Machine parts machining method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a machine part of excellent plane accuracy and roundness even in the case of having a thin-walled annular member as a workpiece. SOLUTION: A workpiece 4 is placed in an unrestricted state on a magnet chuck 6 to obtain unrestricted time machined surface data u (θ) (figure (a)). The workpiece 4 is then restricted by the magnet. chuck 6 to obtain restricted time machined surface data v (θ) (figure (b)). On the basis of the unrestricted time machined surface data u (θ) and restricted time machined surface data v (θ) the cutting feed quantity Z (θ) of a grinding wheel is controlled to grind the end face of the workpiece 4 (figure (c)). When the restricted state of the workpiece 4 is released, warp is formed at a peripheral edge part, while the upper face has fine plane accuracy, and the height of the workpiece 4 from the surface of the magnet chuck 6 is Zo (figure (d)). The workpiece 4 is vertically inverted to grind the other end face (figure (e)).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for machining a machine part, and more particularly to a method for machining a machine part for grinding a surface (a flat portion and a circumferential surface) of a ring-shaped workpiece such as an annular member.

[0002]

2. Description of the Related Art Conventionally, in an annular member such as a bearing ring (an inner ring and an outer ring) of a rolling bearing, a workpiece (hereinafter, referred to as a "work") subjected to a heat treatment is attracted and held by an electromagnetic force of a magnet chuck. Then, the work is constrained by the magnet chuck, and the surface of the constrained work is ground by a grindstone to finish the work to a desired dimensional accuracy.

[0003] That is, since the annular member such as the bearing ring is thin, the work is distorted due to the influence of heat in the heat treatment step which is the preceding step. Therefore, by grinding the flat portion (hereinafter referred to as an “end surface”) or the circumferential surface of the work, the distortion is removed, and desired good flatness accuracy and roundness are obtained.

FIG. 27 is a diagram showing an example of a conventional processing method for grinding a work end face (hereinafter, referred to as a "first conventional technique").

That is, as shown in FIG. 27, when the end face of the work is ground, the work 102 is restrained by the magnet chuck 103 via a thin and easily deformable blotter or a spacer member 101 such as rubber or a thin ring. Then, the magnet chuck 103 is rotated in the direction of arrow a, while the grindstone 104 is rotated in the direction of arrow b and fed in the direction of arrow c, whereby the end face 10 of the workpiece 102 is rotated.
5 is ground. That is, since the work 102 as an annular member such as a raceway is thin as described above, when the work 102 is restrained by the magnet chuck 103, the work 102 is deformed by the attraction force of the magnet chuck 103. easy. Therefore, the spacer member 101 is connected to the workpiece 102 and the magnet chuck 1.
03 to reduce the attraction force of the magnet chuck 103 to the work 102 and
It is intended to avoid deformation of the work 102 by utilizing the elastic deformation of the work 01.

In the first prior art, a grinding wheel 10
By maintaining the "sharpness" of the workpiece 4 in a good condition with a dresser or the like, desired grinding can be performed with a small grinding force F, and thereby the deformation of the work 102 caused by the grinding force F in the direction of arrow c. Is also suppressed as much as possible.

FIG. 28 is a diagram showing an example of a conventional processing method for grinding a circumferential surface of a work (hereinafter, referred to as a "second conventional technique").

That is, in the second prior art, FIG.
(A) As shown in (b), the front shoe 106 and the rear shoe 107 support the outer peripheral surface 108 of the work 102, and the magnet chuck 108 attracts one side surface 109 of the work 102 to attract the work 1.
02 is constrained by the magnet chuck 108, and while the magnet chuck 108 is rotated in the direction of arrow d, the grindstone 110 is fed in the direction of arrow f while rotating in the direction of arrow e.
The outer peripheral surface 108 is ground.

[0009]

However, in the first prior art (FIG. 27), the end face 10
In the case of grinding 5, the deformation of the work 102 on the end face 105 can be suppressed to some extent by weakening the attraction force of the magnet chuck 103 by the spacer member 101 and elastically deforming the spacer member 101. The occurrence of such deformation cannot be completely eliminated. Therefore, when the end face 105 is ground with a grindstone 104 in such a state, good planar accuracy is obtained in a state where the work 102 is attracted to the magnet chuck 103. However, when the suction by the magnet chuck 103 is released, the deformation caused by the suction remains as the deformation of the work, and it is difficult to obtain a mechanical part having a desired excellent flatness accuracy. There was a problem.

In the second prior art (FIG. 28), the elastic deformation is caused by the grinding force of the grindstone 110 in the direction of arrow f and the frictional force generated between the front shoe 106 and the rear shoe 107 and the work 102. There is a problem that a mechanical part having high roundness cannot be obtained with high accuracy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to obtain a mechanical part having extremely excellent planar accuracy and roundness even when a thin annular member is used as a work. It is an object of the present invention to provide a method for processing a mechanical part capable of performing the following.

[0012]

In order to achieve the above object, a method for machining a mechanical part according to the present invention is characterized in that an annular workpiece is restrained by a restraining member and restrained by the restraining member. In the method of machining a machine part, wherein a processing surface of the workpiece is ground with a grindstone, in a state in which the workpiece is unconstrained with respect to the restraining member, the dimensions of the processing surface are measured to perform the unconstrained processing. Surface data is acquired, and in a state where the workpiece is further constrained by the constraining member, dimensions of the processing surface are measured to obtain constrained processing surface data. Grinding the processing surface while controlling at least one of a feed amount of the grindstone in the direction of the work piece or a feed amount of the work piece in the direction of the grindstone based on the work surface data. It is characterized by.

According to the above-described method of machining a mechanical part, the unconstrained state and the constrained surface data of the workpiece are acquired as the unconstrained machined surface data and the constrained machined surface data, respectively. Since the feed amount of at least one of the grindstone and the work is controlled based on the processing surface data and the processing surface data at the time of constraint, it is possible to perform the grinding process in consideration of the amount of change of the work caused by the restraint member, and therefore, the grinding is performed. After processing, when the restrained state is released, it is possible to obtain a machine part with good accuracy (mainly flatness and / or roundness), especially when grinding a thin work that is easily deformed. However, it is possible to obtain a machine component finished with high precision.

For example, when grinding an end face of a work as a processing surface, the height dimension of the work from the constraining member is measured over the entire circumference of the work in the non-constrained state and the constrained state, and machining is performed in the non-constrained state. By obtaining the surface data and the processing surface data at the time of constraint, and performing the grinding processing on the work while controlling the feed amount of the grindstone or the work based on the processing surface data at the time of the non-restraint and the processing surface data at the time of the constraint, a so-called end surface of the work is obtained. Even if "warping" occurs, a mechanical part having good planar accuracy can be obtained after processing.

That is, the present invention provides the above-mentioned processing method, wherein when the processing surface is an end surface, the non-constrained processing surface data and the constrained processing surface data are determined based on a circumferential height of the work. It is characterized by acquiring.

In addition, even if the work is inclined in the non-constrained state, the work does not incline in the constrained state. Therefore, it is preferable to remove such an inclined component from the measured processing surface dimension.

Therefore, the present invention is characterized in that the unconstrained processed surface data removes a tilt component from the measured processed surface dimensions.

When the work surface of the work is a circumferential surface such as an inner surface or an outer surface, the radius dimensions of the work in the non-constrained state and the constrained state are measured to obtain the processed surface data and the constrained data in the non-constrained state. By obtaining the machining surface data at the time and controlling the feed amount of the grindstone or the work based on the machining surface data at the time of non-constraining and the machining surface data at the time of constraining, it has excellent roundness without being affected by the constraining member Machine parts can be obtained.

That is, according to the present invention, in the above-mentioned machining method, when the machining surface is a circumferential surface, the unconstrained machining surface data and the constrained machining surface data are acquired based on a radius dimension of a work. It is characterized by the following.

Further, when the workpiece is eccentric with respect to the axis of the grinding machine in the unconstrained state, there is a possibility that the machining accuracy is deteriorated. It is preferred to remove from.

The grinding apparatus used in the above-mentioned processing method comprises a restraining member for sucking, holding and restraining the end face of the work, and a first reciprocating motion of the restraining member in a first predetermined direction.
Reciprocating mechanism, a grindstone for processing the surface of the work, a grindstone support for rotatably supporting the grindstone, and a second reciprocating mechanism for reciprocating the grindstone support in a second predetermined direction And a rotation processing mechanism that rotationally drives the restraining member, wherein the measuring device measures processing surface data to be processed of the work before and after the work is restrained by the restraining member; and Control means for controlling a feed amount of at least one of the grindstone and the work based on a measurement result of the measurement means.

[0022] The measuring means may be a measuring means for measuring a work surface dimension when the workpiece is not constrained or constrained on the constraining member, and an angle data for measuring a measuring position of the measuring means as angular position data. Measuring means, wherein the control means calculates machining surface data based on the measurement result of the measuring means and the measurement result of the angle data measuring means, and the control means calculates the machining surface data based on the calculation result of the calculating means. It is preferable that a feed amount control means for controlling the feed amount of at least one of the grindstone and the work is provided.

[0023]

Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a plan view of a grinding apparatus (vertical axis type grinding apparatus) used in a method of processing a mechanical part according to a first embodiment of the present invention, and FIG. 2 is a front view of FIG. So,
In the first embodiment, a case will be described in which an end surface of a ring-shaped work is ground.

In FIGS. 1 and 2, a table 1 is mounted on a base 2 and is capable of reciprocating in a horizontal direction indicated by an arrow X. The table 1 has a ball screw (not shown) and a table drive. A servo motor (hereinafter referred to as a “table driving motor”) 3 is used to measure a loading position L (indicated by a dashed line in the figure), which is a mounting position of the work 4, and a measurement position M (to measure a processing surface dimension of the work 4). In the figure, the position indicated by the two-dot chain line) and the grinding position G for grinding the work 4 (indicated by the solid line in the figure) are appropriately moved.

The table 1 is provided with a circular magnet chuck 6 for sucking and holding the work 4 and restraining the work 4, and the magnet chuck 6 is mounted on a work spindle 7. A servo motor (hereinafter, referred to as a “magnet rotation motor”) 8 for rotating and driving the magnet chuck 6 is attached to a base end of the work 4. An encoder 9 for detecting the data θ is provided. A stopper 10 is provided at an appropriate position on the peripheral edge of the magnet chuck 6, and a dresser 11 for truing and dressing the grindstone 5 is provided at an end of the table 1.

A measuring head 12 for measuring the dimension of the work surface of the work 4 is mounted on the base 2 via a support 12a. An end face tracing stylus 13 is attached to the tip of the measuring head 12, and the height dimension (working surface dimension u, v) of the work before and after the work 4 is attracted to the magnet chuck 6 by the end face tracing stylus 13. Measured over the circumference. In the first embodiment, a capacitance type non-contact displacement sensor is used as the end face tracing stylus 13.

The grindstone 5 is formed in a flat plate shape, and is fitted to a grindstone spindle (built-in motor) 14 for driving the grindstone 5 to rotate. The grindstone spindle 14 reciprocates in a vertical direction (indicated by an arrow Z). It is attached to a moving cutting slide 15.

The cutting slide 15 is sandwiched by a pair of support members 17a and 17b fixed to the column 16 with a predetermined preload, and as shown in FIG.
8, a number of rollers 1 held at a predetermined distance from each other.
A rolling guide 9 is provided. That is, the cutting slide driving servomotor (hereinafter referred to as “cutting motor”) 20 is attached to the upper end of the cutting slide 15, and the support members 17 a and 17 b are driven by driving the cutting motor 20. The cutting slide 15 pinched by the roller is guided by the roller 19 to roll and reciprocate in the arrow Z direction.

The cutting slide 15 has a super electrostrictive element 2
1 are accommodated, specifically, as shown in FIG.
The nut bracket 22 is integrally fixed to the cutting slide 15, and the super electrostrictive element 21 is stretchably held between the nut bracket 22 and the flange of the ball screw nut 24 screwed to the screw shaft 23. Have been.

As shown in FIG. 2, a scale 25 with a scale is attached to the column 16, and a linear scale 26 for detecting the scale of the scale 25 is mounted at an appropriate position on the cutting slide 15. ing.

In this grinding machine, when the linear scale 26 detects the scale of the scale 25, the cutting motor 20 is driven according to the detection result, and the cutting slide 1 is moved.
After coarsely moving 5 in the direction of arrow Z, fine adjustment is performed by the superelectrostrictive element 21, whereby the amount of movement of the grinding wheel spindle 14 that moves integrally with the cutting slide 15 is controlled. As a result, the cutting feed amount Z (θ) of the grinding wheel 5 is controlled,
As shown in FIG. 5, the grindstone 5 is fed in the direction of arrow B while being rotationally driven in the direction of arrow A, and the end surface of the work 4 placed on the magnet chuck 6 is ground.

FIG. 6 is a block diagram of a control system of the present grinding machine. The control system 27 measures the measurement result of the end face tracing stylus 13 amplified by the amplifier 28 (the machining surface dimension u,
v), the detection result of the encoder 9 (angular position data θ) and the detection result of the linear scale 26 are input, and a predetermined command signal is supplied to the magnet rotation motor 8, the cutting motor 20, and the superelectrostrictive element 21. Input / output unit 29
And machining surface data u (θ), v based on output results of the amplifier 28 and the encoder 9 input to the input / output unit 29.
(30), a calculator 31 for calculating the amount of fine movement ΔZ of the super electrostrictive element 21 based on the contents stored in the memory 30, a calculation result of the calculator 31 and an angle from the encoder 9. A controller 32 that outputs a predetermined control signal based on the position data θ and the scale data from the linear scale 26.

In the grinding apparatus configured as described above, first, as shown by a two-dot chain line in FIG. 7A, a state in which the magnet chuck 6 is not restrained (hereinafter, this state is referred to as an “unrestricted state”). 7), that is, the dimension u of the work surface in the non-constrained state, is measured by the end face tracing stylus 13, and the measurement result is input to the input / output unit 29 via the amplifier 28. As shown in (b), the encoder 9 detects the angular position data θ indicating the measurement position on the circumference of the non-constrained processing surface dimension u, and the detection result is input to the input / output unit 29. That is, while the magnet rotation motor 8 is being driven, the non-constrained processing surface dimension u is sequentially measured by the end face tracing stylus 13, the angular position data θ is detected by the encoder 9, and the result is sequentially input to the input / output unit 29. You. The input / output unit 29 obtains the unconstrained processed surface data u (θ) by associating the unconstrained processed surface dimension u with the angular position data θ, and stores the result in the memory 30.

Next, as shown by the solid line in FIG. 7A, the height dimension of the work 4 in a state of being restrained by the magnet chuck 6 (hereinafter, this state is referred to as a "restricted state"), The processing surface dimension v is measured by the end face tracing stylus 13, and the measurement result is input to the input / output
Further, as shown in FIG. 7B, the encoder 9 detects angular position data θ indicating the measurement position on the circumference of the processing surface dimension u at the time of constraint as in the case of the non-restrained state,
The detection result is input to the input / output unit 29. That is, similarly to the case of the non-constrained state, the constrained processing surface dimension v
And the encoder 9 detects the angular position data θ, and the result is sequentially input to the input / output unit 29. Next, the input / output unit 29 associates the constraint dimension data v with the angular position data θ and sets the constraint processing surface data v (θ).
And the result is stored in the memory 30.

Next, as shown in equation (1), the arithmetic unit 31 calculates the deviation between the unconstrained processed surface data u (θ) and the constrained processed surface data v (θ), and calculates the deviation of the super electrostrictive element. The fine movement amount ΔZ of 21 is calculated, and the calculation result is supplied to the controller 32.

ΔZ = u (θ) -v (θ) (1) The controller 32 sends the coarse movement amount Z ₀ according to the detection result of the linear scale 26 to the cutting motor 20 via the input / output unit 29. Command and the fine movement amount ΔZ
9 to the super-electrostrictive element 21 via the cutting slide 15.
Is moved to perform grinding by the grindstone 5.

That is, the unconstrained processing surface dimension u and the constrained processing surface dimension v are obtained over the entire circumference at every predetermined angular interval (for example, 1 ′ (minute)) of the angular position data θ of the work. In this case, the cutting feed direction Z at these processing surface dimensions u and v
FIG. 8 shows the relationship between the angle and the angular position data θ. Z =
When 0 is set as the upper surface position of the magnet chuck 6 and the work 4 is ground to a thickness of Z = Z ₀ , the cutting slide 15 (the cutting motor 20 and the superelectrostrictive element 21) is expressed by the formula (2). The cutting feed amount Z (θ) is given as a command value from the controller 32.

[0039] The grinding is performed by positioning the grindstone 5 in the Z-axis direction while rotating the grindstone 5 and the work 4.

That is, the coarse motor Z
₀ is given as a command value from the controller 32, thereby cutting the slide 15 is moved to the position corresponding to Z = Z _0. At the same time, the amount of fine movement ΔZ is given to the super electrostrictive element 21 as a command value from the controller 32, whereby the super electrostrictive element 21 moves in the vertical direction (indicated by the arrow Z in FIG. 2) according to the amount of fine movement ΔZ. Wiggle.

As described above, by changing the cutting feed amount Z (θ) in accordance with the angular position data θ of the work 4, it is possible to perform a grinding process in consideration of the attraction force of the magnet chuck 6, and to improve the planar accuracy. Excellent work can be obtained.

FIG. 9 is a process chart showing the processing procedure of the processing method of the present invention. The processing procedure will be described with reference to FIGS.

First, the surface of the grindstone 5 is subjected to truing and dressing by the dresser 11 to prepare for grinding of the grindstone 5. Next, the table driving motor 3 is driven to move the table 1 in the direction of the arrow X, and the table 1 is stopped at the loading position L. Then, the work 4 is placed on the magnet chuck 6 with the stopper 10 as a reference, and the table 1 is moved to the measurement position M while the work 4 is not restrained. At this time, since the work 4 is in an unconstrained state and is not attracted to the magnet chuck 6, the work has a “warp” as shown in FIG. 9A.

Next, the work spindle 7 is rotated while the measurement position M is in the non-constrained state, and the unconstrained processed surface data u (θ) is measured and calculated, and stored in the memory 30.

Next, the work 4 is restrained by the magnet chuck 6 by operating the magnet chuck 6. At this time, as shown in FIG. 9B, the work 4 is in a state in which the contact surface with the magnet chuck 6 hardly warps due to the attraction force of the magnet chuck 6.

Then, in this state, the work spindle 7 is rotated to measure and calculate the machining surface data v (θ) at the time of restraint, and store it in the memory 30.

Next, the table 1 is moved to the grinding position G,
The cutting motor 20 is driven based on the detection value from the linear scale 26 to coarsely move the cutting slide 15 by the coarse movement amount Z ₀ , and the super electrostrictive element 21 is moved to the fine movement amount ΔZ calculated by the arithmetic unit 31. According to this, the cutting feed amount Z (θ) of the grindstone 5 is controlled, and as shown in FIG.

When the restraint state of the work 4 is released in this state, the warp of the peripheral portion of the work 4 is restored, and as shown in FIG. The upper surface has good planar accuracy, and the height of the work 4 from the surface of the magnet chuck 6 is Z ₀ .

Thereafter, as shown in FIG. 9E, the work 4 is turned upside down, and the other end face is ground. That is, since the grinding end faces in this case a good flatness is in close contact with the surface of the magnetic chuck 6, mechanical components as an annular member having a thickness of Z ₁ having good flatness with a normal grinding wheel feed ( Work 4) can be obtained.

Further, when the work 4 is not restrained,
As shown in (a), when tilted with the tilt amount Δu, the tilt component Δu hardly occurs due to the attraction force of the magnet chuck 6 when the magnet chuck 6 restricts the tilting. The amount of expansion and contraction of the super electrostrictive element 21 is controlled by the amount of fine movement ΔZ to which the amount of inclination Δu that does not reflect the amount of warpage is added. Therefore, when grinding is performed based on the amount of fine movement ΔZ, the non-constrained state is restored. Then, as shown in FIG. 10 (b), the warped state of the other end face becomes a distorted state. Therefore, when the workpiece 4 is turned over to grind the other end face, the processing amount becomes uneven on the surface, and the grinding force F of the grindstone 5 may fluctuate. Therefore, in order to make the grinding force F of the grindstone 5 uniform, it is necessary to perform the grinding with the fine movement amount ΔZ in consideration of the inclination amount Δu. For this purpose, the inclination component is calculated from the unconstrained processing surface data u (θ). It is necessary to remove u ₁ (θ).

Thus, the unconstrained machining surface data u (θ)
Is represented by a Fourier series as shown in Expression (3).

[0052]

(Equation 1)

[0053] Here, a _n is the amplitude of the n-order component, is [psi _n indicates the phase shift. Among them, the slope component u ₁ (θ) is shown in FIG.
As shown in FIG. 1, one cycle of the work (360 °) forms a sinusoidal waveform of one cycle.

That is, as can be seen from FIG.
Since the maximum value P and the minimum value Q of the tilt amount appear once each while the work 4 rotates by 180 °, such n = 1 (primary component) indicates the tilt component u ₁ (θ) of the work 4. . That is, the gradient component u ₁ (θ) is represented by Expression (4).

U ₁ (θ) = a ₁ sin (θ + ψ ₁ ) (4) Here, a ₁ and ψ ₁ are obtained by equations (5) and (6), respectively.

[0056]

(Equation 2)

The values on the right side of the equations (5) and (6) are:
Based on the measurement results of the angular position data θ and the unconstrained processed surface data u (θ) stored at predetermined angular intervals stored in the memory 30, the arithmetic unit 31 calculates a numerical value using a predetermined program prepared in advance. Is calculated approximately.

Therefore, the corrected cutting feed amount Z '(θ) obtained by removing the inclination component u ₁ (θ) from the cutting feed amount Z (θ).
Is represented by Expression (7).

Z ′ (θ) = Z (θ) −u ₁ (θ) = Z ₀ − (u (θ) −u ₁ (θ) −v (θ)) (7) That is, the modified cut By controlling the moving amount of the grindstone 5 based on the feed amount Z ′ (θ), even if the workpiece 4 has the inclination amount Δu before the grinding, the grinding force F can be maintained with a substantially uniform grinding force F. The other end face can be ground.

FIG. 12 is a plan view of a grinding apparatus (vertical axis type grinding apparatus) used in the method of machining a mechanical part according to the second embodiment of the present invention, and FIG. 13 is a front view of FIG. FIG.

In the second embodiment, the grinding is performed by using a cup-shaped grindstone 60 in place of the flat grindstone 5.

That is, also in the second embodiment, similarly to the first embodiment, the processing surface data u (θ), v
After calculating (θ) and storing it in the memory 30, the fine movement amount ΔZ
Then, the magnet chuck 6 on which the work 4 is placed is moved to the grinding position G to perform desired grinding.

In the second embodiment, the work 4 is ground using the tip of the grindstone 33 formed in a cup shape, so that the contact area with the work 4 can be reduced. Therefore, the grinding force F of the grindstone 60 can be reduced.

FIG. 14 is a plan view of a grinding apparatus (horizontal axis type grinding apparatus) used in a method of processing a mechanical part according to the third embodiment of the present invention. The embodiment has two tables (a first table 33 and a second table 34), and the second table 34 is provided with the cutting slide 15 (see FIGS. 1 and 2) in the first and second embodiments. , And FIG. 12 and FIG. 13). That is, the first and second
In the third embodiment, the cutting feed amount Z (θ) of the grindstone 5 is controlled by the cutting slide 15 reciprocating in the vertical direction, whereas in the third embodiment, the second table 34 is controlled.
Is reciprocated in the horizontal direction to control the cutting feed amount Z (θ) of the work 4, thereby achieving the same operation and effect as the cutting slide 15.

Specifically, the base 2 has the second table 3
4 is mounted via a feed screw device (not shown), and the first and second cutting motors 20 are attached.
As in the embodiment, a super-electrostrictive element (not shown) is included therein, and the second table 34 is capable of reciprocating in a horizontal direction indicated by an arrow Z. In addition, the second table 34
A work spindle 7 for rotating the work 4 is provided rotatably. Further, similarly to the first embodiment, a magnet rotation motor 8 and a first encoder are provided at the base end of the work spindle 7. 35 is attached,
Further, a magnet chuck 6 for adsorbing, holding, and restraining the work 4 is provided at a tip of the work spindle 8.

On the other hand, the grindstone spindle 14 for rotating the grindstone 5 is mounted on the first table 33 such that its rotation axis is orthogonal to the rotation axis of the work spindle 7. A measuring spindle 36 is mounted on the first table 33 so as to face the magnet chuck 6, and an end face tracing stylus 37 is disposed at the tip of the measuring spindle 36. A servomotor (hereinafter referred to as “measurement motor”) 38 for rotating and driving the measurement spindle 36 and a second encoder 39 for detecting a measurement angle are disposed at the base end of the motor.

The first table 33 is capable of reciprocating in the horizontal direction indicated by an arrow X via the table driving motor 3 (and a ball screw). The spindle 7 and the measurement spindle 36 stop at the position shown by the solid line so as to be on the same axis, and stop at the position shown by the two-dot chain line so that the grindstone 5 can be cut into the work 4 during grinding.

In the third embodiment, as shown in FIGS. 15 and 16, a pair of left and right work rests 40a and 40b are provided below the position corresponding to the position of the work 4 so as to be able to advance and retreat. ing. That is, in the non-constrained state, the work 4 is supported by the work rests 40a and 40b to prevent the work 4 from dropping downward, and in the constrained state, the work rests 40a and 40b are moved in the directions of arrows H and I. It is retracted in the direction (FIG. 16).

In the third embodiment, the work 4 is ground as follows.

That is, first, after performing a predetermined truing and dressing with the dresser 11, the first table 33 is moved in the direction of the arrow X and the measuring spindle 3 is moved.
6 is moved to a measurement position M (a position where the rotation axis of the measurement spindle 36 coincides with the rotation axis of the work spindle 7),
Next, the work 4 is placed on the work rests 40a and 40b. At this time, the position of the work 4 is adjusted so that the center of the work 4 substantially coincides with the axis of the rotation shaft of the work spindle 7.

Then, the work 4 is moved to the work rest 40a,
The measuring spindle 36 is rotated in the state of being supported by 40b, the end face measuring element 37 measures the non-constrained processing surface dimension u, and the second encoder 39 detects the angular position data θ. The non-constrained processing surface data u (θ) is stored in the memory 30 in the same manner as described above.

Next, after the magnet chuck 6 is operated to bring the work 4 into a restrained state, the work rest 40a,
40b is retracted in the directions indicated by the arrows H and I, and thereafter the measuring spindle 36 is rotated again.
7 measures the constrained processing surface dimension v, detects the angular position data θ by the second encoder 39, acquires the constrained processing surface data v (θ), and stores it in the memory 30.

Thereafter, the first table 33 is moved so that the grindstone 5 comes to the grinding position indicated by the two-dot chain line, and the cutting feed amount Z (θ) is calculated to obtain the second table 3.
4 in the direction of arrow Z, whereby the first and second
As in the embodiment, the grinding process can be performed in consideration of the attraction force of the magnet chuck 6.

As described above, in the third embodiment, the magnet chuck 6 is moved integrally with the second table 34, that is, the work 4 is moved to perform the grinding processing having a desired plane accuracy.

That is, in the third embodiment, the first
Also, unlike the second embodiment, it is not necessary to vertically move the cutting slide 15 in the vertical direction, so that it is not necessary to support the grindstone spindle 14 on a column or the like, and the rigidity can be increased.

FIG. 17 is a plan view of a grinding apparatus (vertical axis type grinding apparatus) used in a method of processing a mechanical part according to a fourth embodiment of the present invention, and FIG. 18 is a front view of FIG. In the fourth embodiment, a case will be described in which the outer periphery of the ring-shaped workpiece 4 is ground.

In the fourth embodiment, the table 41 has a super-electrostrictive element (not shown) and is mounted on the base 2, and the work spindle 7 is rotatable on the table 41. A magnet chuck 6 is fitted to the tip of the work spindle 7, and a magnet rotation motor 8 and an encoder 9 are fixed to the base end of the work spindle 7. And
The dresser 11 is provided at one end of the table 41.

A tracing stylus head 42 is attached to the base 2 via a support base 42a, and a roundness tracing stylus 43 for measuring roundness is protruded from the tip of the tracing stylus head 42. ing. Further, the grinding wheel spindle 14 having the grinding wheel 5 fitted to the tip thereof is disposed in a direction perpendicular to the base 2 so as to be movable integrally with the cutting slide 15 in the arrow Z direction. In the fourth embodiment, the roundness tracing stylus 4
Reference numeral 3 uses a capacitance-type non-contact displacement sensor as in the first to third embodiments.

In the fourth embodiment, FIG.
As shown in the figure, the magnet chuck 6 on which the work 4 is placed is rotated in the direction of the arrow J while being finely moved in the direction of the arrow K by the super-electrostrictive element included in the table 41, and the feed amount Z of the work 4 is cut. While controlling (θ), the outer periphery of the work 4 is ground by the grindstone 5 rotating in the direction of the arrow L.

Next, the processing procedure of the fourth embodiment will be described.

17 and 18, first, the table driving motor 3 is driven to move the table 41 in the direction of the arrow X, then the dresser 11 is set at a predetermined dress position, and the cutting slide 15 is moved to the direction of the arrow Z. The outer surface of the grindstone 5 is trued and dressed by vertically moving in the direction to prepare for grinding.

Next, the table 41 is moved in the direction of the arrow X so that the center of the magnet chuck 6 is located at the roundness measuring position M, and the work 4 is placed on the magnet chuck 6.

Next, a turning drive unit (not shown) is driven to turn the measuring head turning unit 42 as shown by a two-dot chain line, and a roundness measuring element 43 is arranged at a position facing the outer peripheral surface of the work 4. Then, the magnet chuck 6 is rotated while the magnet chuck 6 is in a non-operating state, and the non-restrained processing surface data r (θ) is measured and stored in the memory.

Next, the magnet chuck 6 is rotated with the magnet chuck 6 in an operating state, and the processing surface data s (θ) at the time of restraint is measured and stored in the memory.

Then, the control amount of the table 41, that is, the cutting feed amount R (θ) of the work 4 is calculated based on the unconstrained machining surface data r (θ) and the constrained machining surface data s (θ).

That is, the non-constrained machined surface data r (θ)
And the machining surface data s (θ) when constrained
As in the case of the component, the vibration is calculated as shown in equations (9) and (10).
Width b _n, B_n', An arbitrary angle θ, phase φ, φ'
It is represented by the Lie series.

[0087]

(Equation 3)

However, when the diameter of the work 4 is measured by placing it on the magnet chuck 6, the center of the work 4 and the center of the magnet chuck 6 are usually placed eccentrically. The machining plane data r (θ) and the machining plane data at constraint s (θ) include an eccentric component. The eccentric component is substantially the same as the warp component, as shown in Expressions (11) and (12).
It is represented by primary components r ₁ (θ) and s ₁ (θ) of the unconstrained processed surface data r (θ) and the constrained processed surface data s (θ).

R ₁ (θ) = b ₁ sin (θ + φ ₁ ) (11) s ₁ (θ) = b ₁ ′ sin (θ + φ ₁ ′) (12) Here, the amplitudes b ₁ , b ₁ ′, The phases φ ₁ and φ ₁ ′ are given by the equations (1
3) to (16).

[0090]

(Equation 4)

[0091]

(Equation 5)

Therefore, the non-constrained machining surface data r
(Θ) and the primary component r
By removing ₁ (θ) and s ₁ (θ), that is, the eccentric component, as shown in Expressions (17) and (18), the modified unconstrained machining surface data r ′ (θ) and the modified constrained machining The plane data s' (θ) is obtained.

R ′ (θ) = r (θ) −r ₁ (θ) (17) s ′ (θ) = s (θ) −s ₁ (θ) (18) On the other hand, The radius variation ΔR ₀ (θ) is represented by Expression (19).

ΔR₀(Θ) = r ′ (θ) −s ′ (θ) (19) However, the radius dimension R (θ) of the work 4 is shown in FIG.
The average radius R ₀(Θ) and the average radius R₀(Θ)
Radius variation ΔR₀(Θ) was calculated as the sum of
Accordingly, the radius dimension R (θ) is represented by Expression (20).

R (θ) = R ₀ (θ) + ΔR ₀ (θ) (20) Therefore, such a radius dimension R (θ) is a command value given to the table 41, that is, a cutting feed of the work 4. Quantity R
(Θ).

Then, a turning drive unit (not shown) is driven to turn the measuring head turning unit 42, and the measuring head turning unit 4 is turned.
2 is returned to the original position shown by the solid line and stopped, and then the table 41 is coarsely moved in the direction of arrow X by the table driving motor 3 to move the magnet chuck 6 to the grinding position, and the cutting slide 15 is moved by the arrow. The workpiece 4 is moved in the Z direction, and the outer periphery of the work 4 is ground while controlling the expansion and contraction of the superelectrostrictive element in the table 41 by the cut feed amount R (θ).

When the outer peripheral grinding is completed, the table 41 is moved to the measuring position M, the magnet chuck 6 is turned off, the work 4 is removed from the magnet chuck 6, and the machining process is completed.

Although the relative eccentricity component between the unconstrained state and the constrained state is removed by the above equation (19), the point where the axis of the work spindle 7 and the axis of the work 4 are eccentric is considered. Is not solved, and from the viewpoint of making the grinding force F uniform, considering this point, the radius variation ΔR of the equation (20) is used.
_It is preferable to use a corrected radius fluctuation amount ΔR ₀ ′ (θ) as shown in Expression (21) instead of ₀ (θ).

ΔR ₀ ′ (θ) = r ′ (θ) −s (θ) (21) FIG. 21 shows a grinding apparatus used in a method of processing a mechanical part according to the fifth embodiment of the present invention. FIG. 15 is a plan view of a (horizontal axis type grinding machine), and in the fifth embodiment, two tables (a first table 44 and a second table 61) are provided on a base 2; The grindstone spindle 14 having the grindstone 5 fitted therein is configured to be movable integrally with the first table 44 in the arrow X direction.
4 includes a super electrostrictive element (not shown), which finely moves the super electrostrictive element to adjust the cutting feed amount of the grindstone 5.

A work spindle 7 having a magnet chuck 6 fitted to the distal end thereof is rotatably mounted on the second table 61. Further, a magnet rotation motor 8 and a second One encoder 35 is attached.

Further, a measuring spindle 36 is mounted on the second table 61 so as to face the magnet chuck 6 so that its axis coincides with the axis of the work spindle 7. A probe head 45 having a roundness probe 43 protruded from the distal end thereof is fitted, and a servomotor (hereinafter, referred to as a “rotation drive”) for rotating the measurement spindle 36 is provided at the base end of the measurement spindle 36. And a second encoder 39 for detecting the measurement angle.

Further, in the fifth embodiment, as shown in FIG. 22, a pair of left and right work rests 40a and 40b are provided so as to be capable of moving forward and backward below the position where the work 4 is arranged. That is, similarly to the third embodiment, when the workpiece 4 is in the non-restrained state, the work 4 is moved to the work rests 40a, 40b.
To prevent the work 4 from dropping downward, while the work rests 40a, 40b are retracted in the restrained state.

Then, in the fifth embodiment,
First, after performing a predetermined truing and dressing with the dresser 11, the first table 44 is moved in the direction of the arrow X and stopped at the position indicated by the two-dot chain line, and then the work 4 is placed on the work rests 40a and 40b. Place.
At this time, the position of the work 4 is adjusted so that the center of the work 4 and the axis of the rotation shaft of the work spindle substantially coincide with each other.

Next, the work 4 is moved to the work rest 40a,
The measuring spindle 36 is rotated while being supported by 40b, the roundness measuring element 43 measures the unconstrained measurement data r, and the second encoder 39 detects the angular position data θ. In the same manner as in the embodiment, the non-restrained processed surface data r (θ) is stored in the memory.

Next, after the magnet chuck 6 is operated to bring the work 4 into a restrained state, the work rests 40a, 4a
0b is retracted, and thereafter, the measuring spindle 36 is rotated again, the measurement data s at the time of restraint is measured by the roundness tracing stylus 43, and the angular position data θ is measured by the second encoder 39.
And the non-constrained processed surface data s (θ) is stored in the memory.

Then, the cutting feed amount R (θ) is calculated, and the first table 44 is moved to the position shown by the solid line.
And a coarse movement via a ball screw, and then the radius variation ΔR
_The super electrostrictive element is finely moved based on ₀ (θ), thereby obtaining an annular member as a mechanical part having good roundness.

As described above, in the fifth embodiment, the third
According to the grinding principle substantially the same as that of the embodiment of FIG.
By performing the grinding process on the outer periphery of the above, a mechanical part having good roundness can be obtained.

FIG. 23 is a plan view of a main part of a grinding machine (vertical axis grinding machine) used in the sixth embodiment.
FIG. 4 is a front view of FIG. 23. In the sixth embodiment, a table 62 is provided with a tracing stylus support 46, and the tracing stylus support 46 is provided with an end face measurement at the tip as in the first embodiment. Child 1
The measuring head 12 provided with the projection 3 is mounted, and a turning drive unit 47 is mounted on the measuring element support base 46.
The measurement head 42 provided with a projection is fixed, and the measurement head 42 is configured to be able to turn at a predetermined angle by driving the turning drive unit 47.

The other structure is substantially the same as that of the fourth embodiment (see FIGS. 17 and 18). However, in the sixth embodiment, not only the table 41 but also the cutting slide 15 is used. Also includes a super-electrostrictive element (not shown).

Then, in the sixth embodiment,
Magnet chuck 6 fitted to work spindle 7
The workpiece 4 is then placed on the workpiece 4 and then the unconstrained processing surface data u (θ), r by the end face measuring element 13 and the roundness measuring element 42.
(Θ) and the machining surface data v (θ) and s (θ) at the time of restraint are measured and acquired, respectively, and then the table 62 and the cutting slide are respectively moved to the table driving motor 3 and the cutting motor 2.
0, the workpiece 4 and the grindstone 5 are roughly moved so as to be at predetermined positions, and then one end face is finely adjusted by a super electrostrictive element included in the cutting slide 15 while finely adjusting the cutting feed amount Z (θ). Grinding. After that, the table 62 and the cutting slide 15 are roughly moved again by the table driving motor 3 and the cutting motor 20 so that the work 4 and the grindstone 5 come to predetermined positions, respectively. The outer periphery of the work 4 is ground based on the radius variation ΔR ₀ (θ) by the super electrostrictive element. Then, the work is turned over and normal surface grinding is performed, and the grinding process is completed.

As described above, in the sixth embodiment, the unconstrained machining surface data u (θ), r (θ),
And simultaneously process the constrained processing surface data v (θ) and s (θ), grind one end face, and then perform outer circumference grinding,
Thereafter, the other end face is ground, so that mechanical parts having excellent planar accuracy and roundness can be efficiently obtained.

In the sixth embodiment, as described above, the grinding is performed in the order of one plane, the outer peripheral surface, and the other plane.
The other surface may be changed from the outer surface to the outer surface.In such a case, although the production efficiency is inferior to the former case, since the outer surfaces are ground after the both surfaces are finished with high precision, the outer surface is compared with the former. Can be improved in processing accuracy.

FIG. 25 is a side view of a main part of a grinding apparatus (horizontal axis type grinding apparatus) used in the seventh embodiment. And outer peripheral surface grinding.

That is, in the seventh embodiment, the measuring head 48 is fitted to the tip of the measuring spindle 36, and both the flatness and roundness of the end face can be measured. At 48, the end face tracing stylus 13 and the roundness tracing stylus 43 are attached. A pair of left and right work rests 4 for supporting the work 4 when not restrained.
Reference numerals 0a and 40b are provided at a lower front portion of the magnet chuck 6 so as to be able to advance and retreat in the arrow H direction (and the arrow I direction).

In the seventh embodiment, the sixth embodiment
In the same manner as in the embodiment, both the surface grinding and the outer peripheral surface grinding can be performed substantially simultaneously.

FIG. 26 is a front view of a main part of a grinding apparatus (vertical axis type grinding apparatus) used in the eighth embodiment. In the eighth embodiment, surface grinding and outer peripheral surface are performed. In addition to grinding, the inner peripheral surface can be ground.

That is, in the eighth embodiment, the sixth
In addition to the embodiment described above, an inner grinding spindle 49 having a grindstone 50 for inner peripheral surface fitted to the tip is attached to the table 51, and the inner grinding spindle 49 is pointed to by an arrow via a servomotor 52 and a ball screw 53. By moving in the N direction, the inner peripheral surface can be ground.

Then, in the eighth embodiment,
By substantially the same processing procedure as in the sixth embodiment, the end face, the outer peripheral face, and the inner peripheral face of the work can be subjected to high-precision grinding, and desired mechanical parts can be obtained.

The present invention is not limited to the above embodiment. In the above embodiment, the servomotor is used to roughly move the cutting feed amounts Z (θ) and R (θ) of a grindstone or a work. At the same time, the super-electrostrictive element is controlled by finely moving it. However, it is sufficient if the feed rate Z (θ) and R (θ) can be controlled with high accuracy. It is not limited to. Also, the reciprocating mechanism of each table is not limited to the combination of the ball screw and the servo motor, and it goes without saying that other methods such as a linear motor and a friction drive may be used. Further, in the above-described embodiment, the end face measuring element 13 and the roundness measuring element 43 use the capacitance type non-contact displacement sensor. However, the present invention is not limited to such a displacement sensor. Further, in the above embodiment, the cutting slide is moved by the rolling guide, but it is preferable to use another high-precision moving method such as a static pressure guide.

Further, in the above embodiment, the magnet chuck 6 is used as the restraining member of the work 4, but a vacuum chuck may be used instead of the magnet chuck 6, or a chuck using a claw may be used. Since the amount of deformation due to gripping is considered, there is no problem in principle, and the intended object of the present invention can be achieved.

[0121]

As described in detail above, the method for machining a mechanical part according to the present invention restrains a workpiece formed in an annular shape with a restraining member, and also removes the workpiece restrained by the restraining member. In a method of machining a machine part that grinds a machining surface with a grindstone, in a state where the workpiece is unconstrained with respect to the constraint member, dimensions of the machining surface are measured to acquire unconstrained machining surface data. Further, in a state where the workpiece is constrained by the constraining member, dimensions of the processing surface are measured to obtain constrained processing surface data, and the constrained processing surface data and the non-constrained processing surface data are converted into Grinding is performed on the processing surface while controlling at least one of the feed amount of the grindstone in the direction of the work piece or the feed amount of the work piece in the direction of the grindstone based on the ground surface. Influence of deformation of workpiece Kicking it eliminates, therefore it can be subjected to grinding by maximally utilizing the restraining force of the restraining member, and it is possible to flatness and roundness obtain very good mechanical parts.

[Brief description of the drawings]

FIG. 1 is a plan view of a grinding apparatus used in a method for processing a mechanical component according to a first embodiment of the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is a plan view of a main part of a cutting slide.

FIG. 4 is a front view of a main part of the cutting slide.

FIG. 5 is an enlarged front view of a main part showing a state where a mechanical part is being ground in the first embodiment.

FIG. 6 is a block diagram showing a control system of the grinding apparatus.

FIG. 7 is an explanatory diagram for explaining a processing principle of the first embodiment.

FIG. 8 is an explanatory diagram for explaining a processing principle of the first embodiment.

FIG. 9 is a process chart showing a processing procedure of the first embodiment.

FIG. 10 is an explanatory diagram for describing a problem that may occur in the processing method according to the first embodiment when a mechanical component is inclined.

FIG. 11 is a diagram for explaining a modification of the first embodiment.

FIG. 12 is a plan view of a grinding apparatus used in a second embodiment according to the present invention.

FIG. 13 is a front view of FIG.

FIG. 14 is a plan view of a grinding device used in a third embodiment according to the present invention.

FIG. 15 is a view taken in the direction of the arrows D-D in FIG. 14;

FIG. 16 is a view as seen in the direction of arrows EE in FIG. 15;

FIG. 17 is a plan view of a grinding apparatus used in a fourth embodiment according to the present invention.

18 is a front view of FIG.

FIG. 19 is a main part enlarged front view showing a state where a mechanical part is being ground in the fourth embodiment.

FIG. 20 is a diagram for explaining a modification of the fourth embodiment.

FIG. 21 is a plan view of a grinding apparatus used in a fifth embodiment according to the present invention.

22 is a view as viewed in the direction of arrows WW in FIG. 21.

FIG. 23 is a plan view of a main part of a grinding apparatus used in a sixth embodiment according to the present invention.

FIG. 24 is a front view of a main part of FIG. 23.

FIG. 25 is a front view of a main part of a grinding apparatus used in a seventh embodiment according to the present invention.

FIG. 26 is a plan view of a main part of a grinding apparatus used in an eighth embodiment according to the present invention.

FIG. 27 is a diagram showing a processing method according to a first conventional technique.

FIG. 28 is a view showing a processing method according to a second conventional technique.

[Explanation of symbols]

 4 Workpiece (workpiece) 5 Grindstone 6 Magnet chuck (restraint member) 50 Grindstone 60 Grindstone

Claims (1)

[Claims] 1. A method for machining a machine part, wherein a workpiece formed in an annular shape is restrained by a restraining member and a processing surface of the workpiece restrained by the restraining member is ground by a grindstone. In a state where the workpiece is unconstrained with respect to the restraining member, the dimension of the processing surface is measured to obtain the unconstrained processing surface data, and further in a state where the workpiece is restrained by the restraining member, Obtain machining surface data at the time of constraint by measuring the dimension of the machining surface, and based on the machining surface data at the time of constraint and the machining surface data at the time of non-constraint, the feed amount of the grindstone in the workpiece direction or the machining amount. A method for machining a machine component, comprising: performing a grinding process on the machining surface while controlling at least one of an amount of an object to be moved in the grinding wheel direction.